Preventing preeclampsia and its fetal complications with low-dose aspirin in East Asians and non-East Asians:A systematic review and meta-analysis

Aspirin 75 mg to prevent preeclampsia in high-risk pregnancies: a retrospective real-world study in China

BACKGROUND

Several randomized clinical trials showed that aspirin could decrease the incidence of preeclampsia (PE) in women at high risk, but data from sources other than traditional clinical trials that investigating the preventive effect of aspirin 75 mg on PE is still lacking, especially in mainland China. We aimed to use Chinese real-world data to estimate the preventive effect of low-dose aspirin (LDA) on PE.

METHODS

Clinical data of pregnant women who were at high risk of PE and had their first prenatal visit at the affiliated Taicang People's Hospital of Soochow University during November 31, 2018 and May 10, 2021 was retrospectively analyzed. Among the 266 included pregnant women, 115 individuals treated with aspirin 75 mg per day and the other 151 without such treatment were considered as the LDA group and the control group, respectively.

RESULTS

In the LDA group, 64 (55.65%) of 115 pregnant women took aspirin before 16 weeks of gestation. Besides, 12 (10.43%) and 34 (22.52%) women developed PE in the LDA group and control group, respectively; the aspirin prophylaxis was associated with a lower risk of PE (odds ratio = 0.40, 95% confidence interval = 0.20-0.82, P = 0.0098). In addition, LDA is slightly more effective when initiated before 16 weeks of gestation or in those without chronic hypertension, when compared with their counterparts.

CONCLUSION

Prophylaxis with 75 mg per day of aspirin in high-risk women resulted in a significantly lower incidence of PE than that in the control group.

A randomized controlled trial of low-dose aspirin for the prevention of preeclampsia in women at high risk in China

BACKGROUND

Low-dose aspirin has been the most widely studied preventive drug for preeclampsia. However, guidelines differ considerably from country to country regarding the prophylactic use of aspirin for preeclampsia. There is limited evidence from large trials to determine the effect of 100 mg of aspirin for preeclampsia screening in women with high-risk pregnancies, based on maternal risk factors, and to guide the use of low-dose aspirin in preeclampsia prevention in China.

OBJECTIVE

The Low-Dose Aspirin in the Prevention of Preeclampsia in China study was designed to evaluate the effect of 100 mg of aspirin in preventing preeclampsia among high-risk pregnant women screened with maternal risk factors in China, where preeclampsia is highly prevalent, and the status of low-dose aspirin supply is commonly suboptimal.

STUDY DESIGN

We conducted a multicenter randomized controlled trial at 13 tertiary hospitals from 11 provinces in China between 2016 and 2019. We assumed that the relative reduction in the incidence of preeclampsia was at least 20%, from 20% in the control group to 16% in the aspirin group. Therefore, the targeted recruitment number was 1000 participants. Women were randomly assigned to the aspirin or control group in a 1:1 allocation ratio. Statistical analyses were performed according to an intention-to-treat basis. The primary outcome was the incidence of preeclampsia, diagnosed along with a systolic blood pressure of ≥140 mm Hg or a diastolic blood pressure of ≥90 mm Hg after 20 weeks of gestation, with a previously normal blood pressure (systolic blood pressure of <140 mm Hg and diastolic blood pressure of <90 mm Hg), and complicated by proteinuria. The secondary outcomes included maternal and neonatal outcomes. Logistic regression analysis was used to determine the significance of difference of preeclampsia incidence between the groups for both the primary and secondary outcomes. Interaction analysis was also performed.

RESULTS

A total of 1000 eligible women were recruited between December 2016 and March 2019, of which the final 898 patients were analyzed (464 participants in the aspirin group, 434 participants in the control group) on an intention-to-treat basis. No significant difference was found in preeclampsia incidence between the aspirin group (16.8% [78/464]) and the control group (17.1% [74/434]; relative risk, 0.986; 95% confidence interval, 0.738-1.317; P=.924). Likewise, adverse maternal and neonatal outcomes did not differ significantly between the 2 groups. Meanwhile, the incidence of postpartum hemorrhage between the 2 groups was similar (6.5% [30/464] in the aspirin group and 5.3% [23/434] in the control group; relative risk, 1.220; 95% confidence interval, 0.720-2.066; P=.459). We did not find any significant differences in preeclampsia incidence between the 2 groups in the subgroup analysis of the different risk factors.

CONCLUSION

A dosage of 100 mg of aspirin per day, initiated from 12 to 20 gestational weeks until 34 weeks of gestation, did not reduce the incidence of preeclampsia in pregnant women with high-risk factors in China.

Environmental exposure during pregnancy and the risk of childhood allergic diseases

BACKGROUND

Allergic diseases are one of the most common and important diseases that can exert hazardous effects on children's health. The prevalence of allergic diseases in childhood is gradually increasing all over the world in recent decades. Known causes of these diseases include anomalous immune responses and allergic inflammatory reactions, but the causes of allergic diseases in childhood are complex.

DATA SOURCES

PubMed, Cochrane Library, Embase and Web of Science were searched for articles focusing on environmental exposure during pregnancy and the risk of childhood allergic diseases, including asthma and atopic dermatitis, and the possible underlying mechanism.

RESULTS

In terms of environmental factors, allergic diseases in childhood are closely related to environmental chemical exposure during pregnancy, including bisphenols, phthalates acid esters, perfluorochemicals, polybrominated diphenyl ethers, and polychlorinated biphenyls. However, allergic diseases in childhood are also closely associated with maternal dietary nutrition, maternal intake of drugs, such as acetylsalicylic acid (aspirin), paracetamol and antibiotics, and maternal lifestyle.

CONCLUSIONS

Several harmful environmental factors during pregnancy can result in the interruption of the function of helper T cells (Th1/Th2), cytokines and immunoglobulins and may activate allergic reactions, which can lead to allergic diseases during childhood.

Clinical Procedures for the Prevention of Preeclampsia in Pregnant Women: A Systematic Review

OBJECTIVE

 To identify the most effective procedures recommended for the prevention of preeclampsia.

DATA SOURCES

 A systematic review was performed in the following databases: Pubmed/MEDLINE, CINAHL, Web of Science, Cochrane and LILACS via the Virtual Health Library (VHL). A manual search was also performed to find additional references. The risk of bias, the quality of the evidence, and the classification of the strength of the recommendations were evaluated using the Grading of Recommendations, Assessment, Development and Evaluations (GRADE) approach.

SELECTION OF STUDIES

 In the initial search in the databases, the total number of articles retrieved was 351, and 2 were retrieved through the manual search; after duplicate articles were removed, 333 citations remained. After a thorough review of the titles and abstracts, 315 references were excluded. Accordingly, 18 articles were maintained for selection of the complete text (phase 2). This process led to the exclusion of 6 studies. In total, 12 articles were selected for data extraction and qualitative synthesis.

DATA COLLECTION

 The articles selected for the study were analyzed, and we inserted the synthesis of the evidence in the online software GRADEpro Guideline Development Tool (GDT) (McMaster University and Evidence Prime Inc. All right reserved. McMaster University, Hamilton, Ontário, Canada); thus, it was possible to develop a table of evidence, with the quality of the evidence and the classification of the strength of the recommendations.

DATA SYNTHESIS

 In total, seven studies recommended the individual use of aspirin, or aspirin combined with calcium, heparin or dipyridamole. The use of calcium alone or in combination with phytonutrients was also highlighted. All of the studies were with women at a high risk of developing preeclampsia.

CONCLUSION

 According to the studies evaluated, the administration of aspirin is still the best procedure to be used in the clinical practice to prevent preeclampsia.

Prophylactic aspirin for preventing pre-eclampsia and its complications: An overview of meta-analyses

Benefits of aspirin administration on pre-eclampsia and IUGR depend on the gestational age and dose of aspirin administration. Meta-analyses show that, to prevent preterm labor, aspirin could be administrated even after 16 weeks of gestational age.

Aspirin modulates STOX1 expression and reverses STOX1-induced insufficient proliferation and migration of trophoblast cells

BACKGROUND

A major cause of preeclampsia is the placental ischemia caused by insufficient trophoblast cells, invading into the spiral artery. Storkhead-box protein 1 (STOX1) is highly associated with preeclampsia. Meanwhile, low-dose aspirin for patients with preeclampsia is effective in reducing the incidence of preeclampsia. The aim of the present study was to explore the underlying mechanism, and the relationship between STOX1 and aspirin in preeclampsia.

METHODS

The human choriocarcinoma cell line JEG-3 was employed to mimic trophoblast cells and establish a model for trophoblast cells overexpressing STOX1 and knockdown of JEG cell lines, which were treated with aspirin afterwards. Cell counting kit-8 (CCK-8) assay was utilized to estimate cell proliferation and optimal concentration of aspirin for further experiments. Meanwhile, transwell assay was used to detect migration, and flow cytometry was used to measure apoptosis. Quantitative reverse transcription polymerase chain reaction (RT-qPCR) and Western blotting were applied to analyze the expression levels of STOX1 and related genes.

RESULTS

Overexpression of STOX1 inhibited proliferation of JEG-3 cells through epidermal growth factor (EGF), vascular EGF (VEGF), and transforming growth factor beta 1 (TGF-β1) proteins, while suppressed migration through MMP2, MMP9, and E-cadherin proteins. In contrast, apoptosis of JEG-3 cells was elevated by STOX1 through Bcl-2, Bax, and Cox-2 proteins. Furthermore, we found that aspirin modulated the expression level of STOX1 and reversed proliferation and migration of STOX1-induced insufficient trophoblast cells.

CONCLUSION

The present study suggested that inhibition of the expression of STOX1 could promote the effects of aspirin in the treatment of preeclampsia.

The diagnosis values of serum STAT4 and sEng in preeclampsia

Objective

To detect the levels of signal transducer and activator of transcription 4 (STAT4) and soluble endoglin (sEng) in preeclampsia patients and analyze the diagnostic values of STAT4 and sEng in preeclampsia.

Methods

Fifty‐four pregnant women with preeclampsia from October 2017 to June 2018 were included in this study. Twenty‐eight matched healthy pregnant women were set as the control group. The general clinical characteristics were measured. Serum STAT4 and sEng were detected by ELISA. Correlation between STAT4 and sEng, and their diagnostic value in preeclampsia were analyzed.

Results

Compared with control, the prothrombin time in preeclampsia was significantly lower, while the mean arterial pressure, 24‐hour urine protein, serum creatinine, fibrinogen, and ALT were significantly higher. The circulating levels of STAT4 and sEng were significantly increased in the preeclampsia. The serum levels of STAT4 and sEng in preeclampsia were positively correlated. For the diagnosis of preeclampsia by the serum STAT4, AUC is 0.902, and the sensitivity and specificity are 0.893 and 0.929. By the serum sEng, AUC is 0.873, and the sensitivity and specificity are 0.816 and 0.905.

Conclusion

The serum levels of STAT4 and sEng were significantly increased in preeclampsia with disease severity status, which have promise as diagnostic markers in preeclampsia.

Molecular Targets of Aspirin and Prevention of Preeclampsia and Their Potential Association with Circulating Extracellular Vesicles during Pregnancy

Uncomplicated healthy pregnancy is the outcome of successful fertilization, implantation of embryos, trophoblast development and adequate placentation. Any deviation in these cascades of events may lead to complicated pregnancies such as preeclampsia (PE). The current incidence of PE is 2–8% in all pregnancies worldwide, leading to high maternal as well as perinatal mortality and morbidity rates. A number of randomized controlled clinical trials observed the association between low dose aspirin (LDA) treatment in early gestational age and significant reduction of early onset of PE in high-risk pregnant women. However, a substantial knowledge gap exists in identifying the particular mechanism of action of aspirin on placental function. It is already established that the placental-derived exosomes (PdE) are present in the maternal circulation from 6 weeks of gestation, and exosomes contain bioactive molecules such as proteins, lipids and RNA that are a “fingerprint” of their originating cells. Interestingly, levels of exosomes are higher in PE compared to normal pregnancies, and changes in the level of PdE during the first trimester may be used to classify women at risk for developing PE. The aim of this review is to discuss the mechanisms of action of LDA on placental and maternal physiological systems including the role of PdE in these phenomena. This review article will contribute to the in-depth understanding of LDA-induced PE prevention.

Low-dose aspirin in the prevention of pre-eclampsia in China (APPEC study): protocol for a multicentre randomized controlled trial

BACKGROUND

Low-dose aspirin (LDA) has been proposed as a safe and inexpensive prophylactic agent. Studies in European/Western populations have shown promising results indicating that LDA can reduce the occurrence of pre-eclampsia (PE) in women with identifiable risk factors. However, few controlled trials, particularly large randomized controlled trials, have been performed in Asian populations. The aim of this project is to evaluate the effect of LDA for PE prevention on high-risk pregnant women in China, where PE is highly prevalent and the LDA supply status is commonly suboptimal.

METHODS/DESIGN

An open-label, multicentre randomized controlled trial is being conducted at 13 tertiary hospitals in 11 provinces in China. A total of 1000 eligible women with high-risk factors for developing PE according to their medical histories are being randomized into two groups: a control group (n = 500) and an intervention group (n = 500). Women with high-risk factors, such as a history of PE, chronic hypertension, type 1 or 2 diabetes, advanced maternal age, obesity, family history of PE or nulliparity are eligible. The control group is advised to undergo routine examinations, whereas the intervention group undergoes the routine examinations and receives LDA. LDA (100 mg/d) should be prescribed at night, initiating from early pregnancy (12-20 weeks of gestation) and lasting until 34 weeks of gestation. Demographic data and clinical endpoint outcomes, as well as biological samples (e.g., maternal blood, cord blood, amniotic fluid and placental samples), will be collected. The primary outcome is the occurrence of PE, and the secondary outcomes include maternal and neonatal outcomes and maternal biomarker levels.

DISCUSSION

This is the first and largest multicentre randomized controlled trial to assess the effect of LDA in preventing PE in a Chinese population. The results will potentially influence the prenatal care recommendations in China regarding intervention with LDA for PE.

TRIAL REGISTRATION

ClinicalTrials.gov, NCT02797249 . Registered on 7 June 2016.